EMERGENCE OF AUTOCHTHONOUS CHIKUNGUNYA IN PALM BEACH COUNTY, FLORIDA

POSTER PRESENTATIONS

Background. On July 7, 2014 Florida Department of Health Palm Beach County received a report of a patient that had symptoms consistent with chikungunya fever but denied history of travel outside the USA. On July 17, 2014 the CDC declared this as one of the first chikungunya virus disease cases acquired in the continental United States. Methods. Cases were identified through active and passive surveillance. A field investigation was conducted. All homes within 100 meters of the autochthonous case-patient were visited, residents were interviewed, symptomatic or asymptomatic persons were identified. Risk factors were evaluated; blood samples were obtained from willing participants. An environmental assessment was conducted. Results. By October 4, 2014, through active surveillance four autochthonous cases with chikungunya virus (CHIKV) infection were identified in Palm Beach County, FL. 78 households were visited. No additional symptomatic or asymptomatic persons were identified. A total of eight asymptomatic individuals associated with the first case were tested and none were positive for CHIKV. The field teams identified mosquito-breeding sites on all of the interviewed properties and drained and covered the stagnant water. None of the potential breeding sites contained larvae currently. No CHIKV infections were found to be associated to any of the autochthonous cases. Conclusions. There was no clear epidemiological link established through geo-spatial relationships during incubation and infective periods among imported and/or autochthonous case-patients. Isolation of case-patients during the viremic phase likely diminished transmission risk among household members and local community members. Public Health Implication. If local transmission continues, there is a risk that the virus will thrive and become endemic in these new areas.